In this paper, we conceptualize human-robot interaction (HRI)such that a 3-way relationship among a human, robot and environment can be established. Various interactive patterns that may occur are analyzed on the basis knowledge may be resolved and how shared ground can be established through interactio. We also develop measures to evaluate the interactivities such as an Interaction Efoort, Interaction Stuation Awareness using the information theory as well as Ma
rkovian trasition. An experiment is carried
out in which human subjects are asked to ex
pain or answer abouts through interaction.
The results of the experiments show the fe
asibility of the proposed model and the
usefulness of the measures. It is expected that the presented model and measures will
serve to increase uderstanding of the patterns of HRI and to evaluate the Interac
tivity of HRI system.